Topic: Help!!! My CB559 engine needs to be rebuilt and I've been quoted $1200!!!

[gnanner79]

I'm hoping someone out there will read my desperate cries for help and reply to this posting!  I have a 1974 CB550 that I am converting to a cafe racer.  I have done extensive frame modifications, had a tank and seat made by Benjie from Benjie's Cafe Racers (www.benjiescaferacer.com), installed a CBR600F2 front fork, front calipers, rear calipers, and front and rear rim, installed rear sets from a CBR929, blah, blah, blah, blah!!!  The bike looks phenominal.  When I bought the bike it would start and run for a few seconds (maybe 10) and then die.  The guy I bought it from said that the bike had been stored for about a year and sat on its side stand.  He said it ran, but only on 3 cylinders.  He thought that the # 4 carburetor needed to be rebuilt in order to allow cylinder #4 to fire.  To make a long story short, I am really close to finishing a nearly 1 year project.  I know winter is around the corner and I really want to get this baby up and running soon.  I talked to a local Honda motorcycle mechanic about the situation with the engine and he thought it might be a piston ring issue.  He basically said he wanted to rebuild and jet the cards (due to a higher duration cam and custom exhaust) and replace the piston rings.  I have been quoted $1,200 worst case scenarios, which seems insane!  Any suggestions.  I've considered putting a modified CB450 engine in (Yoshimura big bore pistions, etc) as well as a Cb750 engine.  I've already powercoated my frame, so I hate the idea of starting with a new bike.  I've put a lot of money into this project already and I hate the idea of spending the $1200!  Help please!!!
Shawn

[Raul CB750K1]

$1200 seems to be a pretty common amount lately when it comes to Honda... ;-)


Raul


P.S. Bite the bullet

[Jerry Rxman Griffin aka MuthaF'er]

Get a 2nd opinion with some real time diagnostics!! He did say worse case scenario and that sounds possible if someone else is doing it. If you've done all the work you've stated then you can do a top end job yourself. And for a lot less. The engine guys here can walk you through diagnostics. You could just need a good tune up and not an engine tear down. You'll need a few more tools, plenty of time and much patience. The tools will be a good investment because you will use them again. Your bike sounds nice so it's time to put the finishing touches on it. You might have to save your riding for next spring.  

[ieism]

"He thought it might be a piston ring issue.  He basically said he wanted to rebuild and jet the cards (due to a higher duration cam and custom exhaust) and replace the piston rings"

Don't panic. You probably don't need to spend that much to get it to run. Like RXman said, you can do some of the work yourself.
What makes this guy so sure it's a piston ring anyway? I'd start by only having the carbs rebuild and jetted, and have him do a compression check (or do it yourself).
I recently paid $50 for a carb rebuild, including two new jets and utrasonic cleaning. That price included taking the carbs off, and putting them back in.

[750goes]

Just a quick question..

If you bought it and have done all those modifications to it, how come you did not get the motor running properly in the first place?? thats the most important part that needs to run right, BEFORE you start doing the cosmetically pleasing things..sorry about that, it just seems you have gone ahead and spending money making it look/feel nice without getting it to run nice..

Have you done a compression check or any tune-up since you have had the bike?? it could be something simple like a blocked jet or bad plug etc etc... then you can save yourself a lot of money if you do not need a rebuild.....

[gnanner79]

Thanks for the replys.  To answer the question about the cosmetics vs. running engine, the mechanic at the Honda shop I deal with was swamped, so I figured I would start getting some other things done until he was ready to take the engine.  It became a hassle to get the engine up to him out of the frame, so I decided to finish the frame off and install the engine. 

As far as the piston ring goes, well that's what he thought it sounded like was wrong.  I ran a compression test and I was getting around 110 in the cylinder that won't fire and about 120 in the other 3 cylinders.  I don't know what is a normal reading and I might not have had enough or might have had too much oil in the cylinders during the test.  If anyone can give me a ballpark of what the compression should be. 

The engine would start and idle for a short period of time, but never long enough to really investigate the cylinder issue.  I knew the carbs needed to be rebuilt and I planned on taking them to this guy due to the fact that I can rebuild them but I don't have any experience syncing them.  I think I am going to take the bike up this week to have him do a leak down and inspect the top end.  I agree that after spending all of this time and money already, I really should pay the money to get the bike going.  It just seemed like a lot!  The wallets already hurting!

[750goes]

I would want to do that leak down test, and another compression test at the same time...
If it hasn't been run in a while, it could have a stuck ring, or just need a good run to help it along a bit. Also the carb sync and or rebuild of them will obviously help...

I would hang out for that top end rebuild until you have any other engine issues investigated from a running motor. Pretty hard to tell what is wrong if it does not even idle at the moment...

My compression tests showed from memory 110, 120, 120,130 or something like that, BUT i have since checked the valve clearances which were a fair way off..and I expect those figures to hopefully improve a bit.. also my timing and other issues like gummed up carbs also contributed to the rough idling problems.

Keep at it, it does get better..

[rabidelf]

 Before I sunk $1200 into rebuilding a motor I would try to buy a used, running motor from ebay or someone on this forum for a few hundred bucks for a driver. Then spend a few hundred more rebuilding the old one myself. Pretty glib huh? But honestly it's not rocket science. It sounds like you have set your bike up similar to how I want mine. Do you have any pics of the frame? Any pics of the rearsets on the frame? What are the rim sizes? What kind of tires? Did you cut any lugs off the frame? I just today stripped my bike down to the frame in order to media blast and paint.

[gnanner79]

rabidelf, I get some pics posted in the next week or so.  I am heading out of town and don't have any current pics.  I am using 6-spoke aluminum wheels from a 1994 CBR600F2.  I saw a guy running the same rims on a CB450 at an AHRMA race and thought they looked good.  I basically am going to sandblast them down to the aluminum and clear coat to try to keep as vintage of a look as possible.  The nice thing is, I can upgrade to better radial tires, plus I have converted the rear brake to a disc set up.  I think the rear rim is 4.5" and the front is 3.5".  I am running a 120 series tire on the front and a 150 on the back.  There is sufficient tire clearence, but I have to get the rear cush drive milled down in order for the countershaft sprocket and rear sprocket to line up properly.  Plus, the rear sprocket is about 0.001mm (not kidding, it is really close) from rubbing the inner part of the swing arm.

750goes, at least it sounds like I am getting decent enough compression to potentially rule out any major motor problems.  I'm going to start with the carb rebuild and go from there.  Thanks for the help.